const str = 'hello'
const num = 12312321
const flag = true
const u = undefined
const n = null

const s = Symbol(1)
const s2 = Symbol(1)

const b = 12312312321n


const arr = ['a', 'b', 'c', 'd', 'e',]
// arr[]

const obj = {
    name: '罗总',
    age: 18,
    like: ['running', 'rap'],
    info: {
        city: '南昌',
        girlfriend: 3,
    }
}

const obj2 = new Object()

class Person {

}